BRU PE does not recognize any of our tapes after an upgrade to Yosemite

Last week I did an upgrade to OS 10.10 Yosemite on the host that handles our backups and today I wanted to restore a backup.

When I wanted to access the tape-drive it was not recognized. I realized that it could be that I needed a new 'driver' for our SAS-PCIE controller. So I did an upgrade to it's latest version. After this the tape drive is seen in BRU PE.

The entered LTO-tape is recognized as the right archive but when I try to restore BRU PE tells me that the tape is not a BRU PE Archive and it ejects the tape. When I try to verify the tape (Verify currently loaded tape) it shows the right volume information but when I hit verify the tape rewinds and then I get a message:

Non-BRU Tape
The tape in the drive is not a BRU tape. BRU PE cannot verify non-BRU tapes.

When I hit OK - the only button on the message there is a new error window popping up with just the BRU logo and an OK-button - No text. When I hit the OK-button the window disappeares and leaves a stalled BRU-PE. From this point on I can't do anything than force quitting the application using the finder force quit.

I tried this procedure with 3 different tapes to make sure that I was not having a single defected drive. The issue remained the same.

Has anyone an idea how I can solve this? I can't find anything about possible compatibility issues with OS 10.10 and the Tandberg drive although there TDTool for mac won't open on my system. I'm thus not sure that I don't have to upgrade it's firmware and the actual process of doing that.

I managed to make the host dual boot with an OS 10.8 so I can recover the urgently needed backup. They work like a charm. Running the Bru PE in demo at this time... gives me 30 days to figure out the real problem.

I also made a support ticket to check if the issue is indeed at the RR 2711 at highpoint.